基于LAMP技术检测速冻肉糜类制品中单增李斯特菌的增菌方法研究及应用

岳慧敏; 李海鑫; 罗瑞平; 赵亮

doi:10.13386/j.issn1002-0306.2021050043

基于LAMP技术检测速冻肉糜类制品中单增李斯特菌的增菌方法研究及应用

Study on the Enrichment Methods and Application of LAMP Technology for Detection of Listeria monocytogenes in Frozen Meat Products

摘要

摘要: 本研究比较四种增菌培养基（Fraser、Half Fraser、LB₁、LB₂）对速冻肉糜类制品中单增李斯特菌的增殖效果，评价其对速冻肉糜类制品中单增李斯特菌LAMP检测检出限的影响，并将优化后的增菌条件结合LAMP技术应用于人工污染样本和实际生产线样本检测。结果显示，四种增菌培养基中Half Fraser的增菌效果最好，在6 h内实现单增李斯特菌活菌数从6.4×10¹ CFU/mL 增菌至9.4×10⁴ CFU/mL。结合优化增菌条件后，LAMP检测速冻肉糜类制品中单增李斯特菌的检出限从6.4×10⁴ CFU/g（未增菌）降低至6.4×10¹ CFU/g。利用人工污染单盲样本以及生产线实际样本验证方法的可靠性，结果显示增菌结合LAMP方法与国标法结果一致，准确度100%。该方法样本处理、检测、结果判定总时间控制在8 h内，能够满足企业现场检测需要。

Abstract: In this study efficiency of four enrichment media (Fraser, Half Fraser, LB₁, LB₂) were evaluated for Listeria monocytogenes in frozen meat products, and their effects on the detection limit of Listeria monocytogenes by LAMP were assessed in frozen meat products. Combined with LAMP technology, the optimized method was applied to the detection of artificial contamination samples and samples from production line. The results showed that Half Fraser represented the best enrichment among the four media, which could increase the number of live Listeria monocytogenes from 6.4×10¹ CFU/mL to 9.4×10⁴ CFU/mL within 6 h. The detection limit of Listeria monocytogenes in frozen meat products reduced from 6.4×10⁴ CFU/g (without enrichment) to 6.4×10¹ CFU/g by LAMP with Half Fraser-enrichment. The reliability of the method was verified by using artificial contamination samples and actual samples from production line of the plant. The results obtained from Half Fraser-LAMP were consistent with the results from national standard method with an accuracy of 100%. The whole procedure of sample processing and testing was within 8 h, which could meet the on-site testing requirements of enterprises.